Acquired apraxia of speech is a neurogenic speech disorder that is characterized by:
- erroneous production of speech sounds
- reduced rate of speech
- increased time in transitioning between sounds, syllables, and words
- disordered prosody
May be accompanied by:
- articulatory groping
- difficulty initiating speech
- increasing number of sound errors with increasing word length
- motoric perseverations
Severity ranges from a complete inability to speak to minimal disruptions in speech production.
Primary Clinical Characteristics:
- Slow speech rate:
- Lengthened segments (vowels and/or consonants)
- Lengthened intersegment durations (between sounds, syllables, words, phrases: possibly filled with intrusive schwa)
- Sound distortions (including consonants and vowels)
- Distorted sound substitutions
Errors are relatively consistent in type (e.g. substitution, omission, distortion) and location in repeated utterances
- Prosodic Abnormalities
Nondiscriminative Clinical Characteristics (can occur with phonemic paraphasias):
- Articulatory groping: audible and/or visible and probably disordered relative to the target
- Perseverative errors (perseverations of movement patterns)
- Increasing errors with increasing word length
- Speech initiation difficulties
- Awareness of errors
- Automatic speech better than propositional speech
- Islands of error free speech
References:
- Duffy, J. R. (2020). Motor speech disorders: Substrates, differential diagnosis, and management. Elsevier Health Sciences.
- McNeil, M. R., Ballard, K. J., Duffy, J. R., Wambaugh, J. U. L. I. E., van Lieshout, P., Maassen, B., & Terband, H. (2017). Apraxia of speech theory, assessment, differential diagnosis, and treatment: Past, present, and future. Speech motor control in normal and disordered speech: Future developments in theory and methodology, 195-221.
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